meta-aspeed: drop ASPEEDBASE

This variable is unused.  Drop.

(From meta-aspeed rev: 283c6db2d5b4dfcfa2c1635f7f4180b2ca07bf9a)

Change-Id: I20f37964971717aaa8f79bfb5a7fe381dff5b7e6
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/meta-aspeed/conf/layer.conf b/meta-aspeed/conf/layer.conf
index 8c0d502..55ec1c8 100644
--- a/meta-aspeed/conf/layer.conf
+++ b/meta-aspeed/conf/layer.conf
@@ -8,5 +8,3 @@
 BBFILE_PATTERN_aspeed-layer := "^${LAYERDIR}/"
 LAYERVERSION_aspeed-layer = "1"
 LAYERSERIES_COMPAT_aspeed-layer = "warrior"
-
-ASPEEDBASE = '${@os.path.normpath("${LAYERDIR}/")}'